Short-term follow-up results in 795 nonpalpable probably benign lesions detected at screening mammography

PURPOSE: To evaluate short-term follow-up of nonpalpable probably benign le sions in a 2-year mammographic screening. MATERIALS AND METHODS: Of 13,790 women aged 45-65 years who underwent first -round screening, 795 (5.8%) underwent short-term mammographic follow-up (e very 6 months for 2 years) of nonpalpable probably benign lesions leg, mass es, focal asymmetric densities, and calcifications) previously assessed at an additional imaging evaluation, including ultrasonography. When no change s were found at short-term mammographic follow-up, women were assigned to t he 2-year screening interval: Needle localization and surgical biopsy were performed when the lesion progressed (was enlarged or had an increased numb er or size of calcifications or modification of their initial characteristi cs). The effectiveness of this approach was evaluated with statistical anal ysis. RESULTS: Of 795 lesions, 788 (99%) remained stable, and seven (1%) had chan ges prompting surgical biopsy. Two cancers (0.3%), one microinvasive intrad uctal carcinoma and one 7-mm invasive ductal carcinoma without positive nod es, were found. Four of the five benign histologic results were probably be nign calcifications with progression at short-term follow-up. The sensitivi ty, specificity, accuracy, and positive and negative predictive values were 100%, 99%, 99%, 29%, and 100%, respectively. CONCLUSION: The benign nature of most nonpalpable probably benign lesions c an be typified with short-term mammographic follow-up. This approach permit ted identification of a few low-stage carcinomas, but progression in the pr obably benign calcifications was usually unrelated to malignancy.